I'm going in! After eliminating every option on a SES light code 130 and 134 (O2 sensor intermittant, open) I am replacing the PCM. I direct wired the sensor to the PCM eliminating any possiblity of short or open circuit. This was tested with a brand new OEM sensor. SES off for 2 to 25 min then "boink" on again. My theory is that a board is cracked inside the PCM that causes the loss of continuity.

Ordered a PCM and am having it flashed with all the details that are specific to my car. Mechanically and technically, it appears to be simple. So simple that I am writing this forum to ask what I am missing. Yes , I promise to remove the neg battery cable before surgery.

Love the car, drive 100+ miles a day getting 32mpg and know I can get more. If you have any words of wisdom it would be appreciated.

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The code P0130 is according to the trouble tree would be a bad O2 sensor.
The P0134 can be wiring, sensor ground, terminal tightness O2 sensor or the PCM. Sounds like you have eliminated all but the PCM. It is rare but PCM's can go bad.

...A lousy day in paradise is still a day in paradise.

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I was just doubting he still be getting his posted 32mpg with a bad or intermittant front O2 sensor. Now if the rear O2 sensor was bad...mpg would most likely be unaffected and 32 mpg would be more believeable to me anyway. As he did not mention if the car is a manual or automatic, 32 MPG is not bad at all for an automatic...(my own 97' SL2 automatic gets an overall average of 32 MPG combined city/highway)

The car is an automatic, I have replaced the front O2 sensor (OEM from Saturn) never received any code for second O2 sensor (yes,I realized it was there). Car runs strong, no restriction in Catalytic convertor. Car loves to run. No shorts or ground problems, completely rewired from O2 sensor to PCM. Located and cleaned all ground points in car. Even went so far as to remove all fuses and clean them to assure clean voltage without any loss due to corrosion..........

Keep ideas coming if you have any.

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I drive over 100 miles a day commuting, most of it is highway at 65 to 70. (This calculates out that I spend 22 twenty-four hour days sitting in my car driving back and forth to work each year.) This highway driving helps in the mileage department which again I state is a constant 32 mpg. No complaints here. (Previous car was a 1991 Camry which I drove to a total of 312K miles. 5 sp, original exhaust, original clutch!)

Recent observation.....We have had some really wet weather here and interior of car naturally gets humid when I climb in soaked. When it is damp within car, twice now the SES light has gone off on it's own. My theory is that a trace on one of the boards within the PCM is cracked and the high RH (condensate) helps bridge the crack, creates continuity to a level where Mr. Chip is satisfied with O2 sensor signal. Again, there are absolutely no breaks in the wiring from the O2 sensor and the sensor is good.

chasing a ----->

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Well - surgery is over. Out with old, in with new PCM. All went smoothly. The car started after 3-4 cranks, no SES but had constant on Service wrench. Car ran smoothly, backed it out of driveway and by the time i got to third (auto) the wrench light turned off. I drove about 2 to 3 more minutes and while sitting at a stop light with the directional signal on, the wrench light came back on blinking. Drove about a mile back home, no noticable performance issues, and pulled into my driveway. Turned car off, waited 10 seconds or so, restarted car , no wrench ligh, no issues. Crossed fingers and went to bed.

Up at dawn, jumped into car , started right up and drove the 45 miles to work all highway speeds. Car seems to be running great, no SES or wrench light. Found it a little difficult to drive as I still have my fingers crossed....lol. One question I had was answered, you do not have to worry about the alarm system programming with PCM replacement. There must be a satellite receiver in the alarm module so no reprogramming is necessary.

Feel freee to ask any questions if you have any. This was a very easy mechanical job as long as all static control precautions are practiced. Hat's off to my local NAPA store too. They came through with flying colors and saved me a bundle.

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